The site name is the name you use in the browser to connect to it, without the port number.
As an example, if the URL of the site is http://art.pliant.cx/ then the name of the site is art.pliant.cx and if the URL of the site is http://mysite.mycorp.com:8080/ then the name of the site is mysite.mycorp.com

A site with light green ground is a site that can be accessed on this computer.
You should carrefully check it's various areas definition in order to verify that it does not introduce security holes on the computer.

A site with dull green ground is a site that can be accessed on this computer, but only by users having administrator rights and using Pliant secured channel.